De novo construction of chiral 3‑oxindoles via organocatalyzed enantioselective ortho-Friedel-Crafts addition/novel [1,2]-ester migration

Research Square (Research Square), Год журнала: 2023, Номер unknown

Опубликована: Июнь 20, 2023

Abstract The de novo construction of chiral 3-hydroxyindolenines and 3-oxindoles from easily available starting materials has been highly desired. Meanwhile, the intermolecular enantioselective ortho -C-H addition to ketone carbonyl remains a long-standing challenge. Herein, an unprecedent direct -Friedel-Crafts primary aryl amine with 2,3-diketoesters construct tertiary alcohol disclosed. following unusual [1,2]-ester migration provides family in good excellent yields enantio-selectivity.

Язык: Английский

Silver/Segphos‐Catalyzed Asymmetric 1,3‐Dipolar Cycloaddition for the Enantioselective Synthesis of Pyrrolidine Spirooxindoles

European Journal of Organic Chemistry, Год журнала: 2024, Номер 27(45)

Опубликована: Авг. 26, 2024

Abstract Enantioselective synthesis of chiral heterocyclic derivatives is an important and challenging topic in the field synthetic chemistry. In this work, a silver‐catalyzed asymmetric 1,3‐dipolar cycloaddition glycine iminoesters with 3‐isopropylidene‐2‐oxindoles was developed. The DTBM‐Segphos‐induced spirooxindole reaction used to synthesize range stereodivergent alkyl‐substituted 3‐methylene‐2‐oxindoles, achieving excellent enantioselectivities (up 99 % ee), good diastereoselectivities 20 : 1 dr), high yields under mild conditions. Computational insights from DFT calculations indicate that Michael addition step crucial determining rate enantioselectivity.

Язык: Английский

Miscellaneous (3 + 2) Cycloadditions

Elsevier eBooks, Год журнала: 2022, Номер unknown, С. 215 - 246

Опубликована: Дек. 13, 2022

Язык: Английский